1. Field of the Invention
The present invention relates to a detection apparatus for detecting the change in a magnetic field, and particularly, to a magnetic detection apparatus for detecting the rotation of a magnetic material.
2. Description of the Background Art
As a conventional magnetic detection apparatus, there is disclosed a magnetic detection apparatus including: a magnetic head including a magnetic detection device and magnetic field generation means; a circuit board electrically connected to the magnetic detection device; an inner housing in which the magnetic head and the circuit board are provided; a cap section that covers the magnetic head and has a detection surface; and an outer housing for coupling the inner housing and the cap section (for example, see Japanese Laid-Open Patent Publication No. 2004-309448, paragraphs [0015] to [0022] and FIG. 1).
In addition, there is disclosed a magnetic detection apparatus including: a first block including a magnetic resistance device for detecting the change in a magnetic field, an electronic component that composes a protection circuit against an external noise, a first lead frame electrically connected to the electronic component, and a first base formed by sealing the electronic component, the first lead frame, and the magnetic resistance device by resin; a second block including a magnet, for generating a magnetic field, provided so as to face a subject to be detected, a second lead frame that is electrically connected to the first lead frame and includes a connector terminal for outputting a signal outputted from the magnetic resistance device, to the outside, and a second base formed by sealing the second lead frame by resin; and an exterior resin covering the second block and the first block (for example, see Japanese Laid-Open Patent Publication No. 2004-144601, paragraphs [0007] to [0013] and FIG. 1).
In the magnetic detection apparatus disclosed in Patent Document 1, a lead that composes a connector terminal is formed by insert molding. Therefore, in order to adapt the magnetic detection apparatus to connectors having a variety of specifications, inner housings need to be provided so as to correspond to respective connectors. In addition, the positional relationship between the magnetic detection device and a magnet, which determines the performance, needs to be optimized for each shape of inner housings. In addition, a lead terminal needs to be inserted in a mold when the inner housing is manufactured. Thus, there is a problem that the productivity is limited.
On the other hand, in the magnetic detection apparatus disclosed in Patent Document 2, when insert molding is performed, the second block is once held in a secondary mold by a pin. After the pin is extracted, the position of the magnetic resistance device or the magnet might vary, and there is a possibility that the accuracy of detection is deteriorated. In addition, a sophisticated molding machine is needed because the pin is extracted during molding. In addition, an insert needs to be inserted in a mold when insert molding is performed. Thus, there is a problem that the productivity is limited.